The brown Buick LeSabre careened in reverse toward Joanne White and her 11-year-old son, Jahmara, as they walked hand-in-hand along Lincoln Street in Stoughton on Sunday night.

So Joanne, 3 months pregnant, did what her motherly instincts dictated she do, and yelled at Jahmara: “Run!”

He dropped her hand and fled her side. Seconds later the car hit, shoving her backward. Her son hid behind the nearest tree, the same one the car would hit. He was not hurt.

“She was very protective and very close with him, but this time she told him to run,” said Joan White, 56, Joanne’s mother.

White, a Stoughton resident, was pronounced dead at Massachusetts General Hospital Sunday night. She was 35 and pregnant with her second child.

The driver, Karen Blau, 46, of 10 Suffolk Road, Sharon, has been charged with motor vehicle homicide, operating under the influence of drugs and alcohol and other charges.

White and Jahmara were taking their weekly Sunday night walk from their Grove Street home to her parents’ home on Lincoln Street. The walk is about a quarter-mile, with sidewalks.

White and her son had just left their home when Blau, according to police, backed out of a nearby driveway and sped in reverse across the street, plowing into White on the sidewalk and then the tree.

White’s neighbor, hearing the crash, came running.

“We were screaming, jumping, ‘Help, help, help,’” said Carmen Revera, who lived downstairs from White in a Lincoln Street home. Revera, who witnessed the accident, called White’s family, who rushed to the scene.

White’s father, Joseph White, ran from his home to find his daughter lying in the street.

“If you’re drunk and on drugs, then don’t drive,” said Joseph White, 55, in tears on Monday afternoon. “Your punishment will not be as bad (as mine). I lost a child and a grandchild in one day.”

White was a member of the National Guard and a student at Massasoit Community College. She enjoyed fashion and reality TV.

“She was very polite and everybody loved her. She was a good mother,” said her sister, Philo White, 24.

White enjoyed gathering the family to take professional photographs, and planning matching outfits for each person.

She loved reggae music and the show “In Love and Hip Hop,” her sister said.

“She was loved,” said Joan White. “She had the most beautiful smile I’ve ever seen.”

Neighbors described her as a good housemate and a nice person.

A small memorial appeared Monday morning at the site of the collision, near spray-painted orange circles and symbols left by police investigators. The tree that shielded Jahmara bears a large gash from the car’s impact.

Page 2 of 2 - It’s not the only scar left behind.

“I’m afraid to walk out now. I do a lot of walking,” said neighbor Gloria Avelar, 47, who lives in the house behind the tree. Avelar, who does not drive, set up the memorial for White.

“She was just here, having brunch with a couple of friends,” said White’s mother, Joan. “The day of the accident, her and her boyfriend were picking out names for the baby. We never expected this.”